A leading police officer who was part of the investigation into the fire has branded the diabolical actions of the Philpotts as "stupid" and "shameful".

Assistant Chief Constable Steve Cotterill, of Derbyshire Police, said that not only was the setting of fire itself an "evil" act, but Mick Philpott's reaction to it nothing more than a "sham".

He met the couple on May 16 as they held a press conference, five days after the fatal fire in which the youngsters died. Mairead Philpott was mother to all six, while Mick Philpott was the father of five but had raised Duwayne as his own son.

Mr Cotterill described the behaviour of Philpott that day as the most astonishing he had seen in three decades of policing.

He said: "After 30 years of doing what I do I have never seen anybody having suffered that magnitude of loss deal with it in the manner in which he dealt with it. I would have expected him to be completely and utterly destroyed, and if push came to shove not able to present himself at the press conference."

Question marks around Philpott and his wife's involvement in the fatal fire had already been raised in the minds of police by this time, and witnessing Philpott's performance at the press conference - in which he dabbed at his eyes as with a tissue and buried his face in his hands, but notably no tears fell - was like watching an actor playing a part.

Mr Cotterill sat beside the couple during the meeting with the media, which had been Philpott's idea because he claimed he wanted to thank the public for the efforts they made in trying to save the children.

Mr Cotterill said: "What's going through my head at that point is that I'm torn between trying to care for the parents of six dead children and that, professionally, this is a dilemma.

"I've got that at the back of my mind, I've got managing the press conference, which by any stretch of the imagination is a pretty big press conference, but also looking at what I can only describe as a shameful performance from Mick Philpott - and I stress Mick Philpott because Mairead had virtually buried herself in Mick Philpott - and this dabbing of his eyes with the tissue.